Teletypewriter recording system



Sept. 19, 1944.` P. J. RANK TELETYPEWRITER RECORDING SY-STM FiledMaICh 19, 1943 2 Sheets-Sheet 1 Ptr.' Code Grded. 1 2 3 T Rels.

,mieli @en INVENTOR ATTORNEY Sept. 19, 1944. P. .1. RANKV I TELETYPEWRITER RECORDING SYSTEM 2 sheets-sheet'z Tent/L5 0f' Bour Seector Index lurM/.eot ndex Tentlzso Filed March 19, 1943 Em# Selector mvENToR lfm/zh ATTORNEY Patented Sept. 19, 1944 TELETYPEWRJTER RECORDING SYSTEM Paul Jones Rank, Berwyn,V Ill., assignor to American Telephone and Telegraph Company, a corporation of New York Application March 19, 1943, Serial No. 479,692 I 19' Claims.

This invention relatesto recording systems and particularly to recording systems using teletypewriters as the recording media. Systems suchgas herein disclosed are particularly useful forv recording the operations of telephone lines under service observation, and for recording dat-a with respect to jobs or tasks assigned to Workmen or other employees in factories, offices, machine shops, etc. f

A system of the type to which the improvements invented by applicant are applicable has been disclosed and claimed in U. S. Patent No. 2,278,703, issued April 7, 1942, to G. L. Knittle. The generalpurpose of applicants invention is to improve the lsystem of the Knittle patent and broaden its field of usefulness.

In the system disclosed in the Knittle patent a special recording trunk is provided, and this trunk may be reached by dialing a special number in the automatic P. B. X. system installed in a factory, oioe, machine shop or the like. A teletypewriter, `arranged to print upon a tape, is associated with the recording trunk. After this trunk has been reached by dialing its number, the workman dials his identifying number and the teletypewriter prints the number so dialed. After this number has been recorded the workman dials the number assigned to his job, which is also printed by the teletypewriter.

After these two numbers Vhave been printed, certain clock-controlled apparatus for indicating the time of day is associated with the recording trunk, and this automatically causes the printer to print the time of day indicated by the clock controlled apparatus. In this manner a record is made of the workmans number, the number of his job, and the time that the job was started or finished, as the case may be.

The arrangement disclosed in the Knittle patent above referred to is also adapted for recording the operations of a telephone line to which a service observing trunk has been attached. When the recording trunk, including the teletypewriter, is connected to a Service observing trunk, the teletypewriter will automatically record all numbers dialed by the subscriber of the line under observation.

When the Knittle circuit is used for recording service observations no arrangement is provided for noting the time-of-day. Furthermore, no arrangement is provided in the Knittle circuit for noting (l) the length of the interval occurring between the removal of the receiver from the switchhook and the start of the dialing; (2) the intervals occurring during the dialing of successive digits; and (3) the interval occurring between the end of the dialing operation and hanging up of the receiver at the end ofv a conversation. Y f

The present invention has as its general object the improvement of a recording trunk of the type disclosed in the Knittle patent to overcome the difficulties above mentioned.

Specifically, one object of the present invention is to arrange the recording circuit so that a page printer may be employed instead of a tel etype'l writer printing upon a tape.

Another object is to arrange the recording cuit so that when recording service observations Some character, such as the letter a, or an equiva-y lent symbol, will be printed at Successive time intervals during the period elapsing between the removal of the ysubscribers receiver from his switchhook and the start of the dialing operation.

Still another object is to larrange the trunk to recorda character such as the letter a or its,

equivalent during Ythe intervals between the dial-vv ing operations for the different digits of the dialed number.

A further object of the invention is to print timed characters such as the letter a or its equivalent during the interval between the completion of the dialing operation and the hanging up of the receiver at the end of the conversation.

A still further object of the invention is tol the carriage return and the line feed mecha,

nisms of a page printer will be automatically operated each time the end of aline is reached."y Yet vanother object of the invention is to cause'Y the carriage return and line feed operations to be performed after each time-of-day record when the trunk is used for recording workmens mun# bers and job numbers in shops, factories andthe like.`

One further object of the invention is to pre-.-v

vent the printer from recording a digit dialed during the line feed operation which automati-l cally follows the carriage return operation vin accordance with the present invention.

In accomplishing the elapsed time objectives above enumerated, the printer may be modified v by changing the type bars so that to indicate elapsed time intervals a dot will be printed, for example, instead of the letter a and a dash instead of the letter k.

These objects, and other objects not herein enumerated, are accomplished by the circuit arrangements illustrated in Figures l and 2 of the drawings Yanddescribed in the following description.

In the drawings, Fig. 1 represents that part of the service trunk which is used for printing dialed digits, and for recording elapsed time intervals before, during, and after dialing operations, when the trunk is used either for service observations or for making records of workmens jobs. Fig. 2 illustrates the clock-controlled timerecording arrangements which may be associated with the trunk to print the time of day after certain types of dialing operations.

GENERAL DESCRIPTION oF THE INVENTION The recording trunk disclosed in Fig. 1 terminates in contacts of a nal connector switch so that when the trunk isused for recording the operations of Workmen or employees in factories and the like, access to the trunk may be had by merely dialing a number assigned to the trunk. The trunk has associated With it certain relays and a counting selector switch, including switch elements CS1V and CS2. After connection has been established to the trunk,` these switches will be advanced step-by-step as a digit to be recorded is dialed.. The step-by-step switches CS1 and CS2 control translating relays T1, T2, `T3 and` T4, which operatev to. translate the decimal code used for dialing intoa Baudot code to operate a printer `to print the dialed number.

Page printing apparatus PP may be connected to the translating. relays T1 to T4, inclusive, for recording the dialed digit. As shown, this printing. apparatus includes a start-stop distributor DTR, a motor M for operating the same, a tripping magnet CM for releasing the distributor, anda receiving printer apparatus conventionally represented at RP.

The recording trunk alsoincludes a timing circuit including a cold cathode tube CT and associated. relays 'I'M, TM1 and TMz, which causes the lprinter at successive timedk intervals to automatically print special` symbols, such as the letterafor; if desired, a dot) before, after, and between the dialing of digits by a subscriber whose telephone line is under observation. Arrangements are also provided soy that when such a subscriber is not using his line, the timing apparatus will cause the printer to print another special character such as the .letter k (or, if desired, a dash)y followed by periods or other symbols at successive intervals, at such times as the-telephone circuit under observation is idle. In this manner a record can be made of all elapsed time intervals involved during the use or non-use-of a telephone line under observation.

For making service observations the trunk is provided with conductors c, b, c,1d and e leading operations and elapsed time intervals in connection with the observed line. The service observing apparatus also includes a release key RLSz for releasing the recording trunk from the service observing equipment at the will of an operator.

In connectionwith the recording of workmens numbers and job numbers, the timing apparatus already described may be used for recording elapsed time intervals before and after the dialing operation and elapsed time intervals between the dialing operations for successive digits. In this connection the apparatus associated with the trunk operates to print the letter a or a dot in substantially the same manner as in connection with the recording of similar time intervals switch CRK is arranged to be operated whenever the printer carriage approaches the end of a line. The operation of thiskey automatically setsk in operation a train of relays CB1, CR, LFi, and LF, which function to control the recording printer so that it will automatically perform the carriage return and line feed functions, as will be described in more detail later.

When the recording trunk is used for either recording workmens jobs or for recording the operations of a telephone circuit under service observation, a clock-controlled time recording mechanism is provided to enable the printer to print the time of day. This clock-controlled mechanism is illustrated in Fig. 2. It consists of three main elements-ea time finder selector "IFS, a tenths-of-hour selector THS, and an hour selector HS.

Thehour selector HS consists of four switches or switch banks HSi, HSz, HS3 and HS4, operated' step-by-step so that theswitch advances one point each hour of the 24-hour day. The switches, in cooperation with the other selectors involved, control circuits for printing the digit corresponding to the hour of the day. The switches making -up the hour selector HS are 25-point switches. Twenty-four of these points correspond to each of the twenty-four hours of the Continental day, the extra point being merely pass-by contact over which the switch rapidly steps to start a. new day cycle commencing with the first point.

In order to record the time of day in smaller divisions than hours, a tenths-of-hour selector THS is provided. This includes three sets of switches or switch banks TS1, TS2 and TSa. A fourth switch bank TS4 is illustrated because it is a part of the switch selector unit, but in practice it is not used. These four switches are, like the hour selector, advanced step-by-step, one step for each division of the hour. In the case here assumed the hour is divided into ten G-minute intervals instead of the sixty l-minute intervals used ordinarily in keeping time. This larger interval is used in order to simplify the equipment and because in keeping a recordlof a workmans time a finer division' of the hour is unnecessary.

The tenths-of-hour selector THS controls circuits whereby the recording printer will print digits representing the particular tenth of an hour indicated by the controlling clock, which, by actuating a key switch CT, advances the selectors HS and 'I'I-IS to the positions corre- -quire this. vided, the trunks will all appear upon a certain sponding to -the existing time of day. The switches making up the tenths-of-hour selector THS are 25-point switches. Of these points two groups of ten points each are used for indicating the ten divisions of two successive hours. The remaining points are merely passby positions over which the switch automatically steps to start the next hourly cycle.

The hour selector HS and the tenths-of-hour selector THS are associated with the recording trunk of Fig. 1, and particularly with the printing equipment PP associated therewith, by means of a time finder selector TFS. This time finder selector includes the six switches or switch banks So, So', S1', S2, S3, and S4. These are 22-point switches and the points are divided into two groups of eleven each. One point of each group of eleven is a by-pass position over which the switch advances to start the next cycle. Of the other ten points of each group, eight are used for controlling the successive operations incident to printing the time of day, and these eight points are followed by two points which are utilized to automatically effect the carriage return and line feed operation of the printer. The provision of this feature enables the recording system to employ a page type of printer, rather than a teletypewriter printing upon a tape such as is used with the recording system of the Knittle Patent No. 2,278,703.

When the trunk is used for service observation the time finder selector TFS, the tenths-of-hour selector THS, and hour selector I-ISk are employed to make a record of the time an observed line is released from the recording trunk byv operating the RLSv key. However, when the trunk is used for recording workmens numbers and job numbers, these selector switches automatically come into play to cause the printer to print the time of day after it has printed the numbers of the workman and the job.

OPERATION Further details of the apparatus will be clear from a description of the operation. The operation of the circuit when used for recording workmens numbers and job numbers will be described. This will be followed by a description of the circuit when used for service observation records.

(a) Preparation for dialing A workman desiring to record his number and the number of the job upon which he has commenced work or which he has just finished, will first dial the number which is assigned to the trunk or trunks used for recording purposes. Actually more than one trunk may be provided so that more than' one workman can make a record at any given time if the number of workmen or operatives involved is suflicient to re- In case more than one trunk is prolevelof the final selector of the machine switching system (not shown) and said selector will automatically hunt until it finds an idle trunk or if the trunks are all busy, until it receives a busy signal. Assuming that the trunk illustrated in Fig. l is idle, the wipers of the connector switch come to rest upon the tip, ring and sleeve contacts T, R and S, respectively, shown in Fig. 1. This causes the double wound line relay A to be energized over the workmans line.

Relayv A upon being energized closes a circuit to operate the slow release relay B through its B being suiciently slow in releasing so that it holds up its armature during the momentary interruptions caused by the relay A in response to dialing.

At the front contact of its armature 8b, relay B applies a `busy .ground to the sleeve conductor of the trunk. At the front contact of the armature 3b, relay B connects ground to a tick-took circuit TTC which is set into operation to send tick-tock impulses over the back contact of armature It of relay D, and over' the front contact of armature 6r of' relay B to the tip conductor T of thetrunk. The subscriber upon hearing this signal knowsthat he now. has access to a recordingrtrunk and is ready to dial. The details of the tick-took circuit TTC are not here shown but are fully illustrated and described in the above mentioned Knitue Patent 2,278,703.

Returning to relay B, at the front contact of its armature 8i it prepares a dialing circuit to be described later. At the front contact of its armature 4t it prepares a circuit for operating the selected translating relays T1, T2, T3 and T4 through switches CS1 and CS2 after the digit has been dialed. At its armature Ib, relay B opens the normally closed circuit of the relay TS.

(b) operation of timing circuit If, after the foregoing operations have been completed, the workman does not immediately dial his number, the timing circuit TC cornes into operation; The release of the relay TS disconnects ground over conductors M and 42 and through the resistance r1 from the timing circuit,

thereby causing `the condenser Ct to charge up.'

After theV condenser starts to charge it takes. a definite interval of time, say 11/4 seconds, to reach i a potential suiiicient to break down the gap of the cold cathode tube CT. When the tube breaks down, the condenser` discharges through the tube and operates therelay TM, unless, as will be dej K scribed later, before the tube. breaks down the dialing operation commences. The circuit for the relay TM extends from battery through the re-v of relay TM2 from` battery, through the upper Winding of relay TMz, over the front Contact of armature 2t of relay TM, and thence via conductor to ground over the circuit previously traced for relay TM. Relay TMZ upon operating prepares a locking circuit through its lower winding over the front contact of its armature 2t, and thence through the winding of relay TM1, over conductor m to ground over the right-hand contactof relay P1. This locking circuit is not completed until the relay P1 is operated as will be described later,

Relay TMz at the front contact of its armature 4b completes a circuit to operate the release magnet CM` of the distributor DTR of the printing apparatus PP. This circuit extends from battery throughthe winding of the magnet CM, over the front contact of armature 4c of normally energized.

saidV circuit extending from relay P, over conductor z, front contact of armature 4b of relay TMz, front contact 2t of relay TM, and thence via conductor a: over a path previously traced to ground at the back contact of armature 3b of relay E.

(c) Operation of printing apparatus to record elapsed time 'Ihe energization of release magnet CM releases the rotating arm of the distributor DTR which now commences to revolve. As the brush passes off the start segment sis, the circuit of normally operated relay P is opened and relay P releases. This at once opens the circuit of the release magnet CM so that its latch (not shown) will be able to stop the rotating arm of the distributor When it completes its rotation. At the back contact of its armature 51, relay P completes a circuit for the relay P1 which now operates. Relay P1 at its right-hand front contact connects ground to conductor m and thus completes the circuit previously traced for the locking winding of relay TMz of the timing circuit in series with the winding of relay TM1. Relay TM1 is noW energized and connects ground over its armature 2b, ot, resistance r1, thereby instantaneously completing the discharge of the condenser Ct so that relay TM is released.

Locked up relay TMz at the front contacts of its armatures Bb and 2b connectsground over conductors p and n, respectively, which are connected to segments No. 2 and No. l of the distributor DTR. Consequently, as the distributor rotates it completes a Baudot code combination consisting of marking impulses for segments I and 2 and spacing impulses for segments 3, 4 and 5. This results in the printer printing the letter a or equivalent symbol in accordance with the usual printer code. If it is desired to print a hyphen or a dot to indicate elapsed time the type bar may be changed to print one of these characters instead of the selected letter a. Y

`When arearm of the distributor completes its rotation and comes to rest upon the starting segment ss, relay P is again energized. At the front contact of its armature 4t it again prepares the circuit for the starting magnet CM and at its armature 5t it opens the circuit for the relay P1,

which releases. Relay P1 at its right-hand arma. ture opens the locking circuit previously traced -for the relays TM1 and TM2 in series. These relays are at once released, the relay TM1 again opening the groundconnection over its armature 2b.to the charging circuit forV the cold cathode tube CT.

(d) Repeating operation of the timing circuit until further operation of the timing circuit TC is prevented by the dialing operation, as will be described later. The number of dots printed will indicate the time elapsing between the time the workman takes his receiver oft' the hook and the beginning of the dialing operation.

(e) Dialing operation Upon hearing the tick-took signal previously described, therworkman will ordinarily proceed to dial theY rst digit of his individual number. For each interruption of the dialing circuit the relay A releases its armature. Each time the relay A releases its armature in response to the dialing of the first digit, the stepping magnet STP of the counting selectors CS1 and CS2 is operated over a circuit asfollows: From ground, over the back contact of armature 3b of relay E, over conductor 32, back contact of relay A, front contact of armature 8i of relay B, front contacty of slow release relay B1 (which was operated in parallel with relay B) to point 2 l and thence through the Winding of stepping magnet STP to battery. A parallel circuit extends from point 2l through the Winding of slow release relay C to battery. Relay C is at once energized and remains energized until after the first digit has been dialed. Relay B1, above referred to, being a slow-release relay, like the relay B it remains operated so long as the subscriber has his receiver orf the switchhook.

Relay C upon being operated, at the front contact of its armature 4b, completes a circuit for the sequence relay G1. The function of the sequence relays such as G1, G2, etc., associated with each trunk, is to maintain a busy condition on the trunk after it is once used, until such time as all the other available trunks have been used in sequence. The operation of the sequence relays and their function is fully described on page 10 of the above mentioned Knittle Patent 2,278,703, under the heading Sequential selection of trunks, and reference is made to said patent for further details of the operation of the sequence relays.

At the front contact of its armature 2b, relay C connects ground to the timing circuit TC through the resistance r1 to at once discharge the condenser Ct. If the Workman dials promptly after removing his receiver from the switchhook, this ground connection will be established before the condenser has charged up sufficiently to operate the cold cathode tube CT for the rst time, and the operation of the timing circuit Will be defeated. In this case no dots will be printed by the apparatus PP, and in any event operation of the timing circuit during the dialing of the first digit will be prevented. If, on the other hand, the workman did not commence dialing immediately and one or more dots have already been printed, further printing of dots is prevented when the relay C operates to discharge the condenser Cn and stop the timing circuit in the manner just described.

Each time the armature of the relay A is released in response to dialing, the stepping magnet STP advances the counting selector switches CS1 and CS2 one step. No circuits are operated by the stepping of the counting selector switches until the end of the dialing of the first digit, however. This is because the relay C at its armature 2i prevents the establishment of circuits through any of the translating relays T1 to T4, inclusive, over a path which will be described later.

The operation of relay C at the front contact of lits armature 4t closes the circuit of the relay D as From battery, through the `winding of.

lval the relay C releases its armature.

At its armatures 31 and It relay D opens the tick-teck circuit previously traced to the tip conductor T of the workmans line so that the ticktock signal ceases at the beginning of the dialing operation. Other circuits controlled by the relay D will be described laterV The relay D, locked up as above described, remains operated until the workman, when hanging up, releases therelay B as will appear later.

(f) Translating dialed pulses to printer codes When the rst digit has lbeen dialed the relay A again attracts its armature and holds it upon its front contact so that the circuit previously traced for the relay C is opened. After an inter- At the back contact of its armature 21; relay C, upon releasing, establishes circuits for such of the translating relays T1 to T4, inclusive, as were previously selected by the steppingof the counting selector switches CS1 and CS2.

Let us assume the digit dialed is 6 `so that the counting selector switches CS1 and CS2 are upon their sixth contacts. The circuit for operating the T or translating relays is as follows: From ground, over the back contact of armature 3b of relay E, over conductor fu, back contacts 41 and 6c, respectively, of relays LF' and LF1, over conductor w, back contact of armature 2t of relay C, over the upper closed contact of oit-normal switch ON, over conductor 22 to point 38, over the back contact of armature 2t of relay W to point 23, from point 23 over the front contact of armature 4t of relay B, over conductor 24, over back 'contact of armature 2t of relay HU, thence over the sixth contacts of the counting selector switches CS1 and CS2, respectively, and through the lower operating windings of relays T1 and T4 to battery. At the iront contacts of their 5i armatures, relays T1 and T4 will be locked up over a circuit to be'described later. At point 23 of the circuit previously traced for the T relays, the circuit divides and a parallel circuit is extended over conductor 25 to operate the relay STE, which, by the closing of its armature 2t, initiates the printing operation aboutto be described.

( g) The printing operation fOr dialed digits We now have translating relays T1 and T4 selected and operated. These relays apply ground connections to selected ones of the segments l to 5, inclusive, of the distributor DTR. to print-the digit 6. By reference to the vchart inthe lower right-hand corner of the rst sheet of the drawings, it will be seen that the rst, third and iifth segments of the distributor must be energized in order to print the digit 6. The'i'lrst segment is energized by a connection from ground over the front contact of armature 5b of relay T1. The third segment is energized by a connection from ground over the front contact of armature 5b of relay T4, over the normally closed contacts of the 21 armatures of relays T3, T2 and T1 and thence to said third segment. The fth segment is energized by a connection from ground, over the front contact of armature 21 of relay T4, over the back contact of armaturet of relay T3, over the back contact of armature 2b of relay T2, and thence to said fth segment. Y y

It will be recalled that the relay STE was energized at the same time that the selected T relays were operated. At its front contact relay .STE connects ground to the conductor e', thence over the front contactY of armature 4t of normagnet CM to battery. The release magnet CM releases the arm of the distributor DTR, which commences to rotate, and in so doing prints the digit 6. As soon as the arm leaves the segment ss of the distributor, relay P deenergized, Vand at the back contact of its armature 51 it'connects l ground to conductor 26, which leads to point 28 where the circuit divides, one path continuing tact of its armature 2i. f Said circuit extends fromY ground over the normal back contact of the armature 3b of relay E, over conductor c, back contacts of armatures 4t and 61 of relays LF and LF1, respectively, over conductor w, back contact of armaturen of deenergized relay C, upper front contact of oil-normal switch ON, over conductor 22 to point 3B, over front contact of armature 2e of relay W, over conductor 39, lower front contact of off normal switch ON, and through the winding of release magnet RLS to battery. The counting selector switches are now restored to normal so that the subscriber may proceed to diala new digit, while the distributor *DTR is 'rotating to print the digit previously dialed. ;k

When the brush of the distributor DTR returns to its stop position after having printed the digit previously dialed, relay P is again operated, At its armature 51 relay P opens the circuit pre-V viously traced for the relay W andthe locking circuit for the relays T1 and T4. These three relays are'accordingly restored to normal. Re-

gardless of whether the subscriber is Vdialing a new digit or not. the relay D will still remain locked up and the slow release relay B will stillV be energized. If the subscriber is not dialing, relay A will be energized and relay C will be deenergized.

dots or the letter a, as the case may be, inf the mannerpreviously described, until such-time as the workman starts to dial the secondl digit.A As soon as the workman starts dialing thesecond digit, relay A sends pulses over the circuit pre-v viously described to operate the stepping magnetV STP to advance the counting selector switches CS1 and CS2 to a setting corresponding tothe new digit. During the dialing operation relayC is again energized to hold upiits' armature 2b, thus stopping any further action of the timing circuit TC, by connecting ground over the front ,contact of its armature 2b and through the Yresistance-r1, to discharge Vthe condenser Ct of the timing circuit. The segments of the distributor DTRwill.

be marked in accordance withthe new digit' and the printing operation will take place as before.1

If the workman dials successive digits .ati the normalrate the condenserv Ct lof the timing cir-Y cuit will not have an opportunity to be charged upsuiciently tostart the timing 'circuitintoopera-;

tion to print dots in the manner previously described between the dialing operations for successive digits. When the last digit has been dialed the same condition will exist as previously described after dialing the first digit, namely the relayA will still be energized, relays B and B1 will still be held up, the relay Cwill have been released, and the relay D will remain locked up.

When the workman hangs up his receiver after dialing he releases the relay A. This in turn actuates the relay C, and the stepping magnet STP is operated over the back contact of said relay C by means of a circuit previously described. This causes the counting selector switches to be advanced one step, but they will be immediately released as will presently appear. After a brief interval the slow release relays B and B1 will be released. Relay B at its armature 4t opens the circuit which would otherwise be closed over the conductor 24 to the contacts of the counting selector switches when the relay C releases. This prevents false selection of the translating relays Ti to T4, inclusive. Relay B at the back contact of its armaturelb vcloses the circuit previously traced for the release magnet RLS of the counting selector, which is at once restored to normal. Relay B1 in falling off opens the circuit of relay C, which, after the usualdelay, releases.

It will be noted that in the operations above described no provision is made for separating the digits representing the workmans number and the number of the job upon which he is working into two separate groups. This is unnecessary as in practice it will be understood that each workmansnumber will always havethe same number of digits. If this number is three, for example, the first three digits dialed will always represent the workmans number, while the remgining digits will represent `the number of the jo (i) Preparation, Vof trunk circuit apparatus for time-of-day recording When the relay B is released as above described it will disconnect busy ground from the sleeve conductor of the connector switch over its 8b armature. This permits the release of the automatic switch which established the connection to the trunk. The removal of ground from the sleeve conductor S is only momentary, however, and only long enough to permit the release of the switches, for presently, after the armature of the relay C has fallen 01T, ground will be connected over the normal contact controlled by armature 4b of relay C, over the front contact 21 of locked up relay G1 to point 30, and thence over conductor 3l, over the back contact of the armature 5e of relay D (which releases shortly after the relay B lat its contact Gb opens the locking circuit of relay D), and thence to the sleeve conductor S of the connector switch. Also after relay D is released, a busy 4ground will be applied to said sleeve during such times as the distributor `DTR is rotating. 'Ihis is by reason of the fact that the relay -P is released during the rotation of the distributor, and at the back contact of its-armature I1;V connects ground over conductor 2l to point 30, and thence over conductor 3I and the back contact of armature 51 of relay D to the sleeve S.

It will Vbe noted that the relay D, being slow to release, does not Arelease until ra short interval after the relay B has released. During this interval an operating circuit for the relay E is established from battery through the winding Vof said relay E, over the front contact Vof larmature Int of relay D, over the back contact of armature It of relay B, over conductor I'I, and thence to ground over the idle contact (No. I or No. I2, depending upon the position of the switch) of the switch So of theV time nder selector TFS. In this connection it should be observed that the time finder selector has two idle positions, No. I and No. I2, and it will be in one or the otherof these two positions when it is at rest, depending upon which half of its cycle it last operated over.

(7') Preparation of time finder selector for recording time of vday Relay E upon being energized immediately establishes a locking circuit over the front contact of its armature 8b and the back contact of relay RLS. The relay D does not release until a moment after the relay E has been energized. Consequently relay E at the front contact of its armature Gb closes a momentary stepping circuit for the stepping magnet F of the time nder selector TFS from ground, over the front contact of the armature 4b of relay D, over the front contact of armature 6b of Yrelay E, over the conductor STP', and through the winding of stepping magnet F to battery. This circuit .will be opened as soon as the relay D releases, so that the stepping magnet F of the time finder selector is released a moment after it is energized, and thereby causes the time finder selector to take one step from its idle position. Assuming that the wipers of the switches of the time nder selector had previously been resting on their No. I idle contacts, they will thus be advanced to contact No. 2 with results to be described later.

(k) Operation of tenths-of-hour selector .The purpose of the time nder selector is to connect the time-indicating apparatus with the trunk, and to control the printing of the indicated time in digits representing hours and tenths of hours. Before describing the printing operations t is therefore desirable to understand the operation of the mechanisms which indicate the time of day.

The relayE at its armature Ib disconnects conductor I2 from conductor I3 and thereby prevents any change of the setting of the hour selector of tenths-of-hour selector until the time of day has been printed in a manner to be'presently described. Normally thetenths-of-hour selector is advancedl one step each .time the clock control contact CT Ais closed. The operation of the contactCT closes a circuit 4for the slow operating relay MP. During the short .interval required for the relay lVPto operate a momentary circuit is established from Yground over the lower `contact of the switch CT', over the back contact of the armature of the relay MP, and through the winding of the relay CG to battery. Relay CG is at once locked up over the back contact of the stepping magnet TH of the tenths-of-hour selector THS.

At its upper front contact relay CG connects ground to conductor I3 from which conductor a circuit extends over the back contact of the armature Ib vof relay E (when relay E is not energized), thence over the conductor I2 and any o ne of the contacts 'I to2!! of switch TS1, over the wiper of said switch, and through thel winding of the stepping magnet TH to battery. The steppingV magnet will be energized, thereby unlocking the relay CG, which releases and opens the stepping circuit `iust `traced Vsovthat the tenthsof-hour selector THSis advanced one step. Thus the tenths-of-hour selector -w-ill be advanced a step at a time at the end of every six minutes provided none of the trunks to which it is connected through time finder selectors such as TFS is at the moment printing a time-oi-day record.

vIt any trunk is printing such a record, the circuit just described will be held open at the armature lb of the E relay of such` trunk until the record is completed. Under these conditions the relay CG, which was locked up as previously described when the clock contact CT' operated, will remain locked up over ,the back contact of the stepping magnet TH until the circuit of the said stepping magnet is completed by the release of the armature of the E relay of the trunk which is then printing the tirne-of-day record. When this occurs the time finder selector TPS will be advanced one step although this step will be taken a short interval after the actual tenthsof-hour is indicated by the clock (not shown).

(l) Operation of hour selector The hour selector HS is advanced one step each hour under the control oi the tenths-of-hour selector. Asalready stated the tenths-of-hour selector switches make a full revolution every two hours, taking one step each six minutes. After the expiration of nine-tenths of each hour, a circuit will be completed from ground, over the wiper of the switch TSG, over the ninth or nineteenth contact oi said switch (depending upon the arc in which the switch is being operated), over the contact of key TSK, and through the winding of relay HR to battery. This relay is energized and held up, and so remains until the tenths-of-hour selector advances to its tenth (or twentieth) contact. When this occurs a circuit will be established for the stepping magnet H of the hour selector from battery, through the winding of said magnet, over the front contact of relay HR., over conductor 44 and thence to ground over the upperrfront contact of the relay CG. Thus, at the end of each hour the hour selector HS and tenths-of-hour selector THS will each take one step together and the hour selector HS will be advanced to its next hour indication.

If this step occurs when the tenths-of-hour selector is resting upon its twentieth contact, the switch TS1 of the tenths-of-hour selector is advanced to its twenty-rst contact. An automatic stepping circuit is then formed for the stepping magnet TH which automatically steps the tenths-of-hour selector to its rst position, where it -will be ready to repeat a cycle of operationsv involving another two-hour interval.

(m) Printing first period The time of day will be printed by the printer PP as will be described presently; but to distinguish the digits representing the time of day from those representing the workmans number and his job number, it is desirable that the time-of-day digits should be separated from the digits representing the job number by printing one or more periods before the time of day is printed. As shown, the circuit is arranged to print two periods.

Assuming that the time finder selector was resting upon its first contact when the relay E was energized, it will have been advanced from itsirst to its second position by the operation ofthe stepping magnet F in the manner previously described. In this position ground lconnections are established by the wipers of switches Si, Ss and .S4 to conductors T1', T3' and'Ti, re-

spectively, which are connected to and operate the translating relays T1, T3 and T4.

It will be noted by referring to the counting selector chart at the lower right-hand corner of the first sheet of thedrawings, that relays T1, Ta and T4, when selected, cause the printing of a period. To print this period a circuit is completed by the switch So of the time nder selector for the relay STE, said circuit extending from ground, over the wiper of switch S01, second contact of said switch, over the conductor ,ST, over front contact kof armature 2t of relay E,

over conductor 33 to point 38, thence over the back contact of the armature 2t of relay W to point 23, and iinally over conductor 25, through the winding of the relay STE to battery. The relay STE being operated over this circuit starts the printer into operation and causes the printing of the period recorded by the translating relays T1, T3 and T4, which energize segments.

I, 2 and 4 of the distributor of the printer.

During this printing operation the relay P falls off as usual, operating relay W over its contact 5t and conductor 26, locking the translating relays T1, T3 and T4 over the back contact of its armature 51; and conductors 26 and 29, and establishing a stepping circuit for the stepping magnet F of the time nder selector TFS as follows: From ground, back contact of armature 5t of relay P, conductor 26 to point 28, thence over conductor 34,k front contact of armature 5t of relay E, stepping conductor STP', and through the winding of stepping magnet F to battery. Magnet F moves its pawl to the next ratchet tooth, but relay W performs 4no useful function. At the end of the printing operation the relay P releases and opens the circuits of the stepping magnet F and the relay W.

nder selector..

As soon as the circuit of the stepping magnet F is opened as just described, the pawl oi said stepping magnet advances the time iinder selector TFS from its second to its third position. In this position circuits are again completed over the conductors T1", T3 and T4 (which were unlocked at the end of the previous printing operation by the reoperation of the relay P), and these relays upon being again energized, condition the distributor to print a second period. This printing operation is initiated by operating the relay STE from ground, over the Wiper and third contact of the switch So', and thence over conductor ST' and the circuit previously traced through Y the winding of the relay STE. The falling 01T of the relay P during this yprinting operation again operates relay W (without useful result) and reestablishes the stepping circuit previously traced for the stepping magnet F. When theV relay P is energized at the end of the printing of the secondperiod the circuit of the magnet F is opened and the time nder selector is advanced to its fourth position.

(o) Printing the first "digit of the hour In accordance with the system herein disclosed the twenty-four hours of the day are numbered consecutively beginning with 01 through 23, and

the twenty-fourth hour is numbered 00 instead of 24. To print the complete hour it is therefore necessary to print the hour tenths digit in the" fourth position of the time finder selector, this operation being followed by'the printing of the Y the fifth position ofthe .time

hours unit digit in the distributor.

Upon being stepped to its fourth position, stepping magnet STE is again energized over a circuit from ground, over the wiper and fourth contact ofthe switch So', over the conductorvST and thence over the circuit previously traced through the winding of the relay STE to battery. Relay STE releases the distributor of the printer to initiate the printing operation.

At the same time thev relay STE was energized the segments of the distributor were conditioned to print the tens digit of the hour. Let us assume that the time of day in Continental time is registered by the switches HS and THS as 18.8 hours. The brushes of switches I-IS1,.HS2 and HSs will then be resting upon the eighteenth contact of said switches. The brushes of switches TS1, TS2 and TS3 of the tenths-of-hour selector will also happen to beresting upon` their eighteenth contacts instead of their eighth contacts, if wey assume that the tenths of the even hours are registered in the second portion of the tenthsof-hour selector,.and the tenths of the odd hours in the rst portion.

As the time finder selector is now in its fourth position, the connections from the conductors T4', T3', T2 and T1' are extended through the switches S4, S3, S2 and S1 of the time nder selector to contacts of the hour selector and tenthsof-hour selector. The circuits completed through the four switches of the time nder selector in position 4 will depend upon the tens digit of the hour indicated by the hour selector. In the case assumed the tens digit is l. From switch HS3 of the hour selectorl a circuit is completed from ground, over the eighteenth point of said switch, over conductor I, fourth point of switch S4 of the time finder selector, and over the wiper of Y said switch to the conductor T4', and thence over the circuit previously traced to operate and lock up translating relay T4.

An inspection of the circuit will show that no connections are completed through the switches S3 and S1, over conductors 4 and 9 through any of the switches of the hour selector. Consequently circuits are not completed over conductors T1 Y and T3 to operate the'corresponding translating relays T1 and T3. In the case of switch S2 of the time nder selector in its fourth` position, no conductor is extended to any of the points of the hour selector switches, but instead the fourth point of said switch S2 is grounded. Acircuit is therefore completed from this grounded point over thewiper of the switch S2 to the conductor T3 to operate the translating relay T2.

We now have translating relays T2 and T4 selected. This marks the first, second, third and fth segments of the distributor DTR over circuits which are obvious and need not be traced.

The distributor in the meantime having been released by the operation of the relay STE, rotates and causes the printing` of the digit 1, which, it will be seen from the chart of the count,- ing selector in the lower right-hand corner of the rst sheet of the drawings, results from activating the rst, second, third and fifth segments of (p) Printing second digit of the hour At the beginning of the rotation of the distributor relay P was released as before, to establish a circuit similar to that previously described over the conductor STP for the stepping magnet F. When the relay P is again energized it opens this circuit and 4causes the timefinder. selector T3' to operate the Vrelay T3.

'IFS to be advanced from its fourth to its fifth position.

In this position the units digit of the hour will be printed, this digit being 8 in the case assumed. In position 5 of the time nder selector a circuit is completed from ground, over the wiper ofthe switch HS1 of the hour selector HS,

over the eighteenth contact of said switch, over conductor 5, contact 5 of switch S3 of the time nder selector, and thence over conductor 'Ila' and the circuit previously traced to operate the translating relay T3. At the same time the relay STE is operated over the iifth point of switch Sn and a circuit similar to the circuits previously traced for relay STE, to set the distributor DTR into operation to print the digit 8, this digit being printed when relay T3 alone is selected. It will be noted that in position 5 of the time finder selector no circuits are established over conductors T1', T2 and T4.

(q) Printing third period In a manner` similar to that previously described the time finder selector is advanced to its sixth position at the end of its printing operation for the purpose of printing another period. This period combination is determined by the fact that ground is connected to the sixth contacts of switches S1, S3 and S4 to establish circuits over the conductors T1' T3' and T4. to energize relays T1, T3 and T4. The distributor DTR, of course, starts 'to rotate practically coincidentally with the stepping of the time iinder selector to its sixth position, and the resultant period is printed Yby the printer RP.

(1') Printing the tenths-of-hour digit Next, the time iinder selector is vadvanced to its seventh position, in which it prints the digit represented by the indicated tenth of an hour, which, it will be recalled, was 8 in the case assumed, The tenths-of-hour selector is in its eighteenth position and the time nder selector is, as already stated, in its seventh position, By inspection of the circuit of Fig. 2 it will be seen that no connections are established through the switches S1, S2 and S4 of the time nder selector over the. conductors 3, 8 and Il, respectively, to any live `segments of either of the switches TS2 or TS1; ofthe tenths-of-hour selector. However, a circuit is established from ground, over the brush Vand eighteenth contact of the switch TS2, over. conductor 6, seventh contact of switch S2 of `the time'nder selector, and over conductor The operation of relay T3 applies ground to segments 2 and 3 of the distributor DTR which, during its rotation, causes the printer RP to print the digit 8.

(s) Automatic carriage return The time finder selector is now advanced, in a manner similar to that already described, to its eighth position. In order to use a page printer to makerecords of workmens jobs it is necessary, after the workmans number, his job number, :and the` time of day have been printed, to automatically operate the carriage return of the printer and follow this by the operation of the line feed, to start the next record on a new line. The carriage return operation occurs in the eighth position of the time finder selector. In

this position a circuit is completed from ground,l

overzthe wiper' and eighth contact of switch So of the time finder selector, over conductor CR', to point`3 5, thence over conductor 36 to the fourth Vsegment of the distributor DTR. At thesame time the relay STE will be operated over` the eighth contact of the switch So of the time finder selector. This causes the distributor arm to be released as before. By reference to the chart of the counting selector at the lower right-hand corner of the first sheet of the drawings, it will bev seen that when only the fourth segment of the distributor is energized, no printing operation is performed, but a carriage return operation is initiated by the printer in a manner well understood in the art.

(t) Line feed Yoperation When the distributor DTRV ends the rotation which produced the carriage return operation, the time iinder selector is advanced fromv its eighth to its ninth position, In this position the switch So connects ground over its ninth contact to the conductor LF which leads over conductor 31 to the second segment of the distributor DTR. At the same time relay STE is operated, and the distributor as it rotates, causes the line feed operation as will be clear from the counting selector chart.

(u) Restoring equipment to normal At the end of the line feed operation the time nder selector TFS is advanced from its ninth to its tenth position in a manner similar to the stepping operations previously described. -Relay STE is again energized over the tenth' contact of switch So to start the distributor DTR. As no segments of the distributor are marked, a blank results. Stepping magnet F and relay W are again energized by the falling oil` of relay P. In the tenth position, while relay W is energized, a circuit is established from ground, over the tenth contact of switch So, over conductor RLS', over the front contactV of armature 2b of relay W, and thence through the winding of the relay RLS to battery. At its left-hand contact relay RLS opens the locking circuit for the relayE which is permitted to release. Stepping magnet F is released when distributor DTR comes to rest, and advances time nder selector TFS toits eleventh position. An automatic stepping circuit is at once established for stepping magnet E over the eleventh contact of switch S0', causing selector TFS to be advanced to its twelfth position where'it vcomes to rest. I

Upon being released asabove described, relay E at its armature 9i removes holding ground from the sleeve S of thetrunk, so that the trunk is now free to be again selectedin its order as determined by the action vof theG or sequence relays. The action of the G or sequence relaysl is described under the heading Sequential selec-l, tion of trunks on y'page 10 of the above-mentioned Knittle Patent 2,278,703. At the back con-f tact of the armature 3b relay E applies ground toll the back contact of relay A so that the latter is now in condition to receive dialed impulseson a subsequent call.

Finally, by closing the backcontact of armature Ib, relay E prepares a circuit for the stepping magnet TH for the tenths-of-hour selectorl over conductors l2 and I3 so that on theopera-ll tion of the relay CG in response to the-,clockop erated switch CT, the tenths-of-hour selector can be advanced to the next tenth of an hour.

. Such action would be prevented during the timerecording operations Ypreviously described because during these operations,l the relay E held the stepping circuit of thev magnet TH open,A

`(v) .Automatic separation of twenty-four hour periods so that it Awill automatically cause the printer to print thetime at the end of each 24-1f1'o11r d ay.

This result is obtained by connecting ihewinding of the relay Dover conductor Itito the twenty-third point of switch HS4 ,of the hour selector HS, and by connecting the brush of this switch over conductor 46 to the contact of the relayHR. Whenthe hour selector HS and the Ytenths-ofhour selector THS indicate that the time is 23.9 of the Continental day,r4 ground will be connected over the ninth contact of the switch TS3 of the tenths-of-hour selector THS to operate the relay HR. Relay HR is thus energized and remains held up until the tenths-of-hour selector 'IHS advances to its tenth contact. f

When this occurs the clock contact CT operates the relay CG in the manner previously described. Relay CG locks up over the back contact of the stepping magnet TH, and at its upper'Y front contact relay CG connects-ground over conductors I3 and YI2 as previously described to operate the stepping magnet 'II-I. Relay CG also applies groundover' its .upper front contact, over conductor 44, front contact of relay HR, and thence through the winding of stepping magnet H of the hour selector HS to battery; Consequently the stepping Vmagnets H and TH are `operated. simultaneously, the one to move the wiper' of switch HSi of hour selector -1-IS,.over

conductor I6, and through the winding of relay D to battery. The relay D is thereby energized.

VThis energization is only momentary, however,

for the relay HR is released as soon asthe tenthsof-hour selector THS is vadvanced from itsninth to its tenth position, and this opens the circuit above traced for the relay D. Nevertheless, the momentary operation. of the relay D is long enough to cause the relay E to be energized and locked up over jcircuits previously traced under headings (i) and (7') above. This sets the time finder selector TFSr into operation to control the printing of the digits oo o to which selectors Hs and THS are set, thus recording the end of the Continental day. The printing of these digits will take place in a manner similar to the printl ing operations described under the above headings (y) to (r), inclusive. Y

(aa) Service observation-Preliminary operations telephone line which is under service observation.

I n order that'the trunk may be employed'for This may be accomplished by arranging the time-indicating apparatus of Fig. 2

service observation conductors a, b, c, d `and c are associated with certain relays and relay contacts of the trunk of Fig. 1, and these Afive conductors are connected to ve conductors leading into the service observation apparatus SO, shown within the dotted rectangle in the upper righthand corner of Fig. l. This service observation equipment SO includes a dial pulsing relay DPR, whose contact is connected over the conductor e' to operate the relay A of the `trunk in response to dialing operations; The service observation equipment also includes a release key RLS and a relay OBR for restoring the trunk apparatus to Vnormal when it Ais no longer being used for service observation.

In practice when a subscribers line is associated with the service observation equipment SO,

the relay DPR is connected so that Vit is energized whenever thetelephone subscribers line circuit is closed, and it responds tordial pulses. 'Ihe sys-- tem is also designed so that a dash orv equivalent symbol, followed by a succession of periods, will be printed at all times when the line under observation is not being used either for dialing or talking. Dots or equivalent symbols will be printed, however, during the talking periodA and during periods intervening between dialing operations.

When the service observation equipment SO is connected to a telephone line to be observed and the line is at the time not in use,rthe subscribers circuit will be open and therefore the relay DPR will be deenergized. In order to start the recording trunk to printing a dash or other symbol Vfollowed by periods, the operator actuates a key (not shown) to cause momentary operation of the relay DPR. This closes a circuit over the conductor e through the upper winding of the relay A of the trunk circuit and causes momentary actuation of the relay A... Relay A upon being energized causes relays B and B1 to be operated in the manner already described in connection with the recording of workmensoperations.

Relay B upon being operated performs 'one Y function not hitherto described. It closesat the A falls off after the momentary operation of the Yrelay DPR of the servceobservation equipment,

relayB remains energizedV and stays energized so long as the'service observation equipment is connected to the trunk. Relay B1, however, after being'momentarily energized by relay A, permits its ,armature to fall oiT shortly after its circuit is opened by the release of relay A.

During this brief interval following the release of relay A and beforethearmature of relay B1 falls o, the operating circuitlior relay C and the stepping circuit for stepping magnet STP of the counting selectorwill ube closed. Both of these circuits have been previously traced and pass from conductor 32 over the back contact of relay A, over the front contact of armature 8c of locked up relay B, and over the front contact of relay B1 to point 2|, and thence in parallel through the windings Vof relay C and the stepping magnetzSTP. After a moment these circuits are opened by the release of the slow release relay B1, and-both relay C and the steppingmagnet VSTP become deenergized. In the meantime, vhow- Y ever, the stepping magnet STP has advaned the' counting selector one step so that the off normal switch ON lis closed.

:The closure of the off normal switch does not Operate the release magnet RLS in this instance,

however, as the circuit of the release magnet,

which extends over the lower contact of off-normal switch -ON and overjconductor 39 to the back contact of armature Ib of relay B is held Open by locked upY relay B. Consequently, the counting selector, which has been advanced one step, remains so advanced until it is released by the action of the relay W, as will be described later.

(bb) .Service observation-Printing elapsed time symbols when Zine is idle In the meantime while relay B remains energized, relay B1 falls oi after the momentary actuationof the linerelay A as already described. This completes a circuit for the relay HU over the back contact of the relay B1 as follows: from ground, Vover the back contact of armature 3b of relay E, over conductor 32, over the backeontact of relay A, front contact of armature 8u of locked up relay B, back contact of relay B1, and thence over conductor and through the winding of relay I -IU to battery. Relay HU, when operated, remains operated so long as the telephone line under observationis not in use, for under these conditions the relay A will be released and, conse- `quently the relay B1 will also be released, although the relay B will remain locked up as already described. Y

Relay HU upon being energized opens at its arma-ture 2t the marking circuit controlled by the counting selector switches CS1 and CS2. At the upper front contact of itsarmature 6b it connects ground over conductor 41 to conductor 36 and thus marks the fourth segment of the dis- 40 tributor. At the front contacts of its armatures 2b and 4b relay I-IU operates translating relays T3 andV (Tf1, respectively, over the following circuits: From ground, over the back contact of armature 3b ofrelay E, over conductor v, over back contacts of armatures 41 and Bt of relays LF and LFi', respectively, over conductor w, over the back Contact of armature 2t of relay C, over the upper contact of the oi normal switch ON, over conducto 22toV point 38, thence over back contact of armature 2t of relay W to point 23, thence over thefront contact of armature 4t of locked up relay B, over conductor 24 and over front contacts'of armatures 2b and 4b of relay HU through the windings of relays of T3 and T1, re-

spectively. It will be' notedthat the circuits just tracedfdepend upon the fact that switch ON is oifnormal.

As will be seen by reference to the chart of the counting selector shown in the lower righthand corner of Fig. 1, the energization of relays T1 and Tamarks the rst, second and third contacts ofthe distributor. VSince the front contact of armature 6b of relay HU marked the fourth segment of the distributor, we now have the rst four segments of the distributor DI'R, marked. Relay C when released by release of relay B1 as previously described, sets the distributor into operation by operating relay STE, over a path from ground at 3p of relay E, over conductor v, over back armature contact 4t of relay LF, back armature contact 6i of 'relay LF1, over conductor w, over back armature contact 2t of relay C, over upper contacts of switch ON, over conductor 22 -to point 38,Y over back armature contact 2t of relay W to point 23 thence'over conductorV 25 and through the windng of relay STEL-to battery, operating relay STE. Relay STE in operating "causes the distributor to rotate' as already dekarmature contacts. This causes relay TS to operate and disable the timing circuit, causing'the "release magnet RLS tov bey actuated over a circuit extending from battery through the` winding of said magnet, over the lower contact of ol normal switch ON, over conductor 39,1front contact of thea'rmature 2t of relay W to point 38, over conductor 22, over the upper make contact of off normal switch ON, over the back contact'of armature 2t of relay C, .over conductor w, and

' thence over a circuit previously traced to ground via the back contact of armature 31;;of relay E. 'Ihe magnet RLS releases the counting selector which is restored to normal and opens the oi normal switch.

When the distributor completes its revolution relay P is again energized and releases relays W,

T1, T3 and TS. Release of relay TS permits the timing condenser CT to 4charge and breakdown tube CT as before described. 1 This energizes relay TM and starts the cycle of the timing circuit as already described, to once more release the Vdistributor and cause it to rotate.

.the'upper' contact lof the oi normal switch. Therefore, segments I,-2 and 4 only of the distributor are marked, with the result that for this cycle of the timing circuit TC' and for successive cycles thereof a period will beprinted.

Periods will continue to be printed until the telephone subscriber of the observed line dials another subscriber as will be described later. Consequently, the interval of time after lthe telephone line is connected to the service observation circuit SO and until the subscriber dials a number, is indicated by-a dash followed at equal successive intervals by periods. This indicates to the observer, who knows the time between successive periods, the total time which has elapsed between putting the line under observation and the rst dialing operation. 1 Y

(cc) Service observation-Recording dialing and talking periods of Zinc tributor DTR so that it on the observed line' takes up'the line for use by removing the receiver from the switchhook, the conditionv 'changes so that the timing circuit now `V`causes the printer 'to print dots or hyphens invstead of periods.

This change in operation arises from the fact that when the subscriber takes his receiver 01T the switchhook the relay DPR is energized and in turn operates therelay A. Relay'A by removing its armature from its back contact immediately opens the circuit previously traced for the relay HU,which releases and at its armature 6b removes the marking ground from the fourth segment of the distributor DTR. Relay A in turn closes a circuit previously traced for operating "the relay B1, which by removing its armature from its back contact`holdsV open the circuit of the relay HU at another point. Said armature of relay B1 at its* front contact prepares the circuit for the relay C, which, however, is not Yoperated at this time because its circuit (previously traced) is held open by the armature of energized relay A. Y Y

Relays TS and C, therefore, both remain released so that the timing circuit TC continues to operate cyclically in the manner previously described. However, since at this time the relay HU is releasedfonly the first and second seg'- ments of the distributor DTR are marked. Hence the printer successively prints the letter-a (or, if the type bar is altered, a hyphen) at intervals determined bythe timing circuit TC. The printing'of'dotscontinues until the subscriber commences to dial another station.

When this occurs relay DPR of the service observation equipment will intermittently fall off and cause the intermittent release of the relay A in response to the dialing of the first digit. fRelay B1 remains energized during the pulsing ,op- 40' eration duev to dialing, and consequently the relay C is energized over a circuit previously traced via'the front contact of Vthe armature of relay B1, front contact of armature 8p of relay B, and over the back contact' of relay A to conductor 32. 1 y

As previously explained, relay C when thus en-v ergized remains energized during the dialing of the rst digit. At the front contact of its armature 2b' it applies ground to conductor '42 to stop further operation of the timing circuit during the dialing of the rst digit. Relay C. at the frontcontact of its armature 41-1cauess relay D to be pulled 'up as previously described in con-v nection with the dialing of workmens numbers and job numbers. Consequently,-the dialing operation Causes the counting selector switches CS1 and-CS2 to function as previously described to selectively operate certain of the translatingl relays T1 to T4, inclusive, thus marking the diswill cause the dialed digit to be printed.

At the end of the dialing of the first digit relay C is released. Consequently, if the subscriber delays dialing the second digit, the timing cir,- cuitwillcome into operation andr cause hyphens or dots to be printed again.A When the next digit is dialed relay C will again be energized,l the timing circuit will be disabled, and the next digit will'be recorded as before.

W'hen `the last digit has `been dialed, relay DPR of the service observation equipment will remain energized while the calling and 'called' subscribers are talking. Relay A willrtherefore vbe held up and after a short interval the Vrelay Cwill berreleased. Relay D,.however, will re.-Y

'mainlockedlurp Vover the front contact of Iarmature :6b of relay B and will remain locked up --while the line is under serviceobservation.

- VRelay C upon falling off removes lthe ground over condu-ctor 42 from the timing circuit, ,so

`that the timing circuit again commences to repeat ritscycle. Since the circuit of relay HU is held .open by the armature of relay B1 which is .still energized; the timing circuit marks the printer over conductors n and p to send hyphens fat successive timed Vintervals during the period `between the dialing of the last digit and the time .that 'the subscriber hangs up.

When the subscriber hangs up, relay DPR is lreleased and it in turn releases relay A, which.

.opens the circuit of relay B1. As relay B1 `is slow to release, its armature does not fall off yimmediately and `during this brief interval circuits previously traced for relay C and for the stepping magnet STP of the counting selector i are established over the front contact of the armature of relay B1, over the front contact of armature 81; of relay B, and oyer the -back vicontact of armature of relay A to conductor 32.

This causes the counting selector to advance one T3 and T1 to be actuated. These two relays mark segments vI, `2 and 3 of the distributor DTRY so :that now theY first four segments are energized, and the distributor causes a distinctive. character such as 1/2 to be printed under the control of the timing circuit TC which was started into -operation when relay C was released.

While this character is being printed relay W isenergized in a manner` previously described,

.and at the front contact of itsarmature 21 completes a circuit previously traced for the release .magnet RLS, which restores the counting selector (which had previously taken one step) to normal. Relays T1 and T3 are released at the end of the vprinting operation, and cannot again be energized over the front contacts of armatures 4b and 32h of relay HU, because their circuits pass over contacts of the off normal switch ON which are now open. Consequently, as the timing circuit TC continues to operate, .relay TMz marks the first andsecond contacts of the distributor Y while the relay HU at the front contact of its armature Bb marks the fourth contact of the distributor. Therefore, during further cycles of the timing''circuit TC the printer prints periods to indicate'the interval elapsing between the hang;

ing up of the receiver at the end of the last conversation, and the removal of. the receiver from the hook again to make a new call.

When the trunk is no longer to be used for service'observation, the service observer operates the release key RLS' and thereby completes a circuit for the relay OBR from ground, over said release key RLS', over conductor a, front contact of armature 8b of locked up relay D,.over conductor d, and through the winding of relay OBR to battery. Relay OBR is energized and locks up over its upper contact so long as the key RLS' is held closed. At its lower armature relay OBR opensthe locking circuit of the relay B which was previously ytraced over conductors c and b,

relay OBR is deenergized and all of theequipment =is now :restored to normal.

`(dei) Service obserziatz'o-Automat'ic carriage return j During a serviceobserving operation the-printfer aprints a continuous succession of characters consisting of a dash followed by successive periods -whenthe line is not in use,and dialed digits and hyphens when the line vis in use. It is therefore evident that if a page printer `is employed, it .Willbenecessary'each'time the record reaches fthe end of 1a line, to cause -an 4automatic Acarriage return operation to take place, and -follow this `by a -linefeed operation, thus enabling the record to vbe continued on the succeeding line. In order fto' accomplish vthis result. the printer Icarriage is arranged to operate ra key CRK when the end of :a line is reached. The .operation of this 'switch -opens the energizing circuit for'the relay TM of vthe timing circuit which was previously traced over conductors and't, thus preventing further operation of the timing circuit after the Atiming cycle then taking place has been `completed.

The operationof the switch CRK completes a circuit'for .the relay CR1, over a circuit from battery, through the Winding of said relay, over the switch CRK, over conductor -t, thence over'conductor "v, and over the back contact of armature '3b of Arelay E to ground. If at the time the switch CRK is operated the distributo1` is rotating to cause the printing of the last preceding character of the record, the relay -P will be in its deenergized condition and will hold open the 'circuit of commutator magnet *.CM. As soon, however, as the relay'P pulls up at the end of the rotation of the distributor, commutator magnet CM is operated `by a circuit from ground over the front contact of armature `2b lof relay CR1, over conductor e' relay P1.

and over the' front contact of armature 41of relay vPthereby releasing the brush arm of the distributor4 DTR. n

Therelay P is released as soon as the distributor starts into operation Vand operates the At its left-hand front Contact relay P1 connects ground over conductor y, over the back contact of armature 2t of relay LF1, over the front contact of armature 2t `of relay CR1, through the resistance r3 and the winding of the relay CR to battery. Relay CR upon being energized, locks up over a circuit from battery, through its winding, through resistance r3, over the frontcontact of armature 4b of relay CR, over back contact of armature 21 of relay LF1, over conductor y and left-hand armature of relay P1 to ground. Relay CR connects ground over the front contact of its armature 2t, over the back contact of the armature 21 of relay LF, and thence over conductor over conductor CR to point 35, and finally over conductor 36 to the fourth segment of the distributor DTR. During the rotation of the distributor only its fourth segment is marked, and this causes the distributor to select and set into operation the carriage return mechanism in a manner well understood in the art.

The operation of relay CR also prepares a circuit for relay LF1, said circuit extending from ground, over the front contact of armature 4t of relay CR, through the winding of the relay LF1,

and through the resistance r3, and through the winding of relay CR to battery. Relay LF1 is prevented from operating at this time, however, as

:asserisce` its winding is short-crcuited by a connection ex-V tending from the upper terminal of its winding, over the front contact of armature 4b of'relay CR, over the-backV contact of armature 2t of relay LF1, over conductor y, and over the front left-hand contact of relay P1 to ground. When relay P1 is released by the energization of relay P at the end of the carriage return operation, the short-circuit above traced about the winding of relay LF1 is opened by relay P1, and relay LF1 becomes energized. The carriage return operation, of course, restores switch CRK to normal and thus opens the circuit of relay CR1, which is now released.

Yee) Service observation-Automatic line feed The operation of relay LF1 connects ground over the front contact of its armature 2b, over conductor z', and over the circuit previously traced through the winding of the commutator magnet CM. This circuit is established as soon as'relay P is again energized after the carriage return operation and releases the distributor DTR to perform the line feed operation in a manner about to be described. As soon as the commutator starts rotating for the line` feed operation, relay P is released, thus again operating the relay P1, which at its left hand front contact connects ground over conductor'y,V over the front contact of armature 2t of relay LF1, and through the winding of relay LF to battery.

Relay LF upon operating locks up over a circuit from battery, through its winding, over the front contact of its armature 4b, and over conductor y and left-hand front contact of relay P1 to ground. Relay LF is thus held locked up dur-L ing the rotation of the' distributor. At the front contact of its armature GbreIay'LF short-circuits the winding of relay CR by means of actinnection from battery, over the front contact of .armature 6b of relay LF to the common junction of resistance r3 and the winding of relay CR. Relay CR is accordingly released and its armature 4c opens the circuit of relay LF1.

At its armature 21; relay LF opens the previously traced marking circuit for the fourth segment of distributor DTR, and at the front contact of its armature 2b relay I F establishes a new marking circuit from ground over conductor s, conductor LFand conductor 31 to thersecond segment of the distributor DTR. During this operation of the .distributorV DTR only its second segment is marked, and it therefore selects and operates the mechanism for causing a line feed operation to take place in a manner well understood in the art. At the end of this operation the relay P is again energized, thus releasing relay P1 and opening the previously traced locking circuit of relay LF at the vleft-- hand armature of relay P1.

(if) Preventing interference ,from dialing during carriage reruml and Zine feed Arrangements are provided for preventing false operation of the printing equipment due to a digit being dialed by the subscriber of aline under observation while the carriage return and line feed operations, above described, are taking place. When the distributor DTR is rotat-A ing during the carriage return operation the relay P is released and consequently the relay W is energized over a circuit previously traced. Dialed impulses during the carriage return operation operate the stepping magnet STP: to

g claims.

pass 'through the contacts ofthe switches CS1 andCSz, and thence over the back contact ofV armature 2t of relay HU, over conductor 24, front contact of armaturet of relay B, to point 2,3, and then over the front contact of armature 2t ofrelay W toV point' 38, over conductor 22, over the upper contact of off normal switch ON, over back contact o f armature 2t of relay C, over conductor tu, back contacts of armature Bt and (It 'of relays LF1 and LF, respectively, over conductor v and back contact of armature 3b of relay E to ground. This circuit, however, is held" open during thecarriage'return operation byrelayW.

At' the vcompletion of the carriage return operation, relay P is again energized and releases relay W, but it also simultaneously releases the relay P1, which in turn removes the short-circuit previously traced for the winding of -relay LF1.A Relay LF1 operates and at its armature 61; opens the circuit above traced for the translating relays at another point. Relay LF, which as above described was operated immediately after relay LF1, also Vholds open the energizing circuit for the translating relays T1 to T4, in' elusive, at its armature 4t. Consequently none of -the translating relays can be actuated to mark the segments of the distributor DTR in accordance with the dialed impulses coming in over the line, until relays LF1-and'LF have both beenreleased b y the left-hand armature ofrelay Y.P1 falling. off at the end of the'line feed operation. f Y.

The above describedV carriage return and line feed operations are not ordinarily used in recording-workmens numbers and the numbers of ingline.

It will be understood that the automatic separation of twenty-four periods, as described under heading (v) above, will come into play at the end of each Ydayin connection with the making of records of service observations, as well as in connection with the recording of workmens identification numbers and job numbers.

While this invention has been described in certain specic arrangements which are deemed desirable, it will be .obvious that 'the generalV principles herein set forth may be embodied in many other organizations widely 'different from those illustrated, Without departing from the spirit of the invention as defined in the appended VWhat is claimed'is:

.1. In a recording system, a recordingtrunk having a teletypewriter connected therewith 'and adapted to lbe associatedl withlatelephone line hayingla receiver and a dial, means to receive dial signals4 fromy saidn line and record them as digits by means otsaid' teletypewriter, and means to cause said teletypewriter to print timed symbols after the telephone subscriber removes Vhis receiver from the switchhook and until dial'- ing commences.

2`.In a recording system, a recording trunk having a' teletypewriter connected therewith and adapted to be associated'with' a telephone line having are'ceiver and a dial; means torreceive dialsignals from said line and record them as digits'by means of said teletypewriter, and means to cause said' teltypewrite t0 print timed sym-y bolsfb'etwen the dialing operations for successiveldig'its.v Y

3`In`a recording system, 'a recording trunk havg'a teletypwlitei cnncted therewith and adapted vto be associated with a telephone line having a.' receiven'and a dial,` means to receive dial s'ig'nals representing digits from said line, means to convert said dial signals' into corresponding printing telegraph signals representing gaat@ finden over said t'eisen-drie line; andi niese trolled' by said timing'devi'cefor causing'said-teletypewriter to printA special" symbols between Vthev dialing operations for successive digits.

7. In a recording' system','a` recordingY trunk having a'. teletypewriter connected therewith andV adapted to' be associated with a telephone line having a receiver and a dial, means to receive dial'signals representing digits from said line,l means to convert said dial signals into correspondingprinting telegraph signals representing digits, Vmeans to record the latter signals as digits by means of said teletypewriter, a timing device operable in successive timed cycles' during periods digits, means to record the latter signalsas digits by meansfof said teletypewriter, and means to cause said teletypew'r'iterA to continuously print uniformly timed'symbols'after'the dialing opera tions and before the" hanging up of the receiver by the' telephone subscriber. 'l

4. In a recording system, a recording trunk having ateletypewriter connected therewith and adapted to be associated with a telephone line having a receiver and a dial', meansto receive dial signals representing digits from said line; means Y x to convert said dial signals into' corresponding printingr telegraph signals representing' digits, means to record theY latter signals as digits by means of said teletypewriter, a timing device operabler in successivetimed cyclesV during periods when said'trunkl is associated with a telephone linev and dial signals' are not beingtransmitted over said telephoneline; and-means controlled' by said timing device for causingsaidteletypewriter to print specialv syrnbols each time saidy timing device operates through its cycle. I

5; In a recording system, a recording trunk` having acteletypewriter connected therewith and adapted to be associated with a vtelephone line having a receiver and a dial', means to receive dial signalsV representing digits from said line, means to convert said dial signals into corre'- sponding printing telegraph signals representing digits, means to record the latter signals as digits by means of said teletypewriter, a timing device operable in successive timed cycles during periods when said trunk is associated with a telephone line and dialsignalsare not being transmitted over said telephone line, andV means controlled by said timing device for causing said teletypewriter to continuously print uniformly vtimed special symbols after the telephone subscriber removes his switchhook-V and until dialing com-V mences.

6. In a recording system, a recording trunk periods when said trunk is associated with a telephone line and dial signals are not being transwhen said trunk is associated with a telephone line and dial signals are not being transmitted over said telephone line, and means controlled by saidV timing device for causing' said teletypewriter tol' continuously print uniformly timed special symbols after the dialing operations and before the hanging up'of the receiver by the tele'-` phone subscriber.

8.V In a recording system, a recording trunk having a teletypewriter connected therewith, aV telephone'line having' a receiver and a dial, means to receive dial signals representing digits from said' line, means to convert said dial signals into corresponding printing' telegraph signals representing digits, means to record the latter signals as digits by means of a teletypewriter, service observing' equipment for associating said telephone line with said trunk, and means causing said teletypewriter to continuously print a special symbol at uniformly timed intervals whenthe Vis associated withy said telephone line through said service' observing equipment and tnelneis not inV use:

H911 In' 'aA recording system, a recording trunk having a teletypewriter connected therewith, a telephone' having a' receiver and a-dial, service observing equipment for associating said te1e.

phone line with said trunk, means causing said teletypewriter toprint a special symbol at timed intervals when the trunk is associated with said telephone line through said service observing equipment and the line is not in use, andmeans tov cause said teletypewriter to print a different symbol at timed vintervals after the Vtelephone i subscriber removes his receiver from the switchhook and until dialing commences.`

10; In a Vrecording system; a recording trunk having a teletypewriter connected therewith, a

u telephone having a' receiver and a; dial, service` observing equipment for associating said telephone linewith said trunk, means-causing said teletypewriter to print a special symbol at timed intervals when the trunk is associated with said telephone line through said Vservice observing equipment and the line is not in use, and means to cause said teletypewriter to print a different symbol a timed intervals between the dialing operations for successive digits.

`11. In a recording system, a recording trunk having a teletypewriter connected therewith, a telephone having a receiver and a dial, service observing equipment for associating said telephone line with saidl trunk, means causing said teletypewriter to print a` special symbol at timed intervals when the trunkis associated with said telephone line throughsaid service observing equipment and the line is not in use, and means to cause said teletypewriter' tol print a diierent symbol at timed intervals after the-dialing operationsland` before thehanging up of the receiver by the telephone subscriber.

means to receive dial signals from said line and telephone line having a receiver and a dial, means to receive dial signals from said line and record them as digits by means of said teletypewriter, means to cause said teletypewriter to printthe time of day after a succession of dial signals have been received, and means to cause said teletypewriter to execute a carriage return operation and a line feed operation after recording the time of day.

14. In a recording system, a recording trunk fhaving a page-type teletypewriter connected therewith and Yadapted to be associated with a telephone line having a receiver and a dial, means to receive dial signalsY from said line and record them as digits by means of said teletypewriter, means to cause said teletypewriter to print the time of day after a succession of dial signals have been received, means to cause said teletypewriter to execute a carriage return operation and a line vfeed operation after recording the time of day,

and means causing said teletypewriter to print the time of day at the end of each day.

15. In a recording system, a recording trunk having .a teletypewriter connected therewith and adapted to be associated with a telephone line having a receiver and a dial, means t receive dial signals representing digits from said line, means to convert vsaid dial signals into corresponding printing telegraph signals representing digits, means to record the latter signals as digits by means of said teletypewriter, and means causing said teletypewriter to automatically print the time of day at a predetermined time each day.

16. Inra recording system, a recording trunk having a page-type teletypewriter connected therewith and adapted to be associated with a telephone line having a receiver and a dial, means to receive dial signals from said line and K record them as digits by means of said teletypewriter, means causing said teletypewriter to print special symbols at timed intervals when the trunk is associated with said telephone line and dial signals are not being transmitted over the line,

and means to cause said teletypewriter to auto` matically execute :a carriage return operation at the end of each line. e

17. In a recording system, a recording trunk having a page-type teletypewriter connected therewith and adapted to be associated with a telephone line having a receiver and a dial, means to receive dial signals from said line and record them as digits by means of said teletypewriter, means causing said teletypewriter to print special symbols at timed intervals when the trunk is associated with said telephone line and dial signals are' not being transmitted over the line, and means to cause said teletypewriter to automatically execute a carriage return operation and a line feed operation at the end of each line.

18. In a recording system, a recording trunk having a page-type teletypewriter connectedv therewith and adapted to be associated with a telephone line having a receiver and a dial, means to receive dia-1 signals from said line and record them as digits by means of said teletypewriter, 4

means causing said teletypewriter to print special symbols a timed intervals when the trunk is associated with said telephone line and dial signals are not being ytransmitted over the line, means to cause said teletypewriter to automatically exetherewith and adapted to be associated withaV telephone line having a receiver and a dial, means to receive dial signals from said line and record them as digits by means of said teletypewriter, means causing said teletypewriter to print special symbols at timed intervals when the trunk is associated with said telephone line and dial signals are not being transmitted over the line, means to. cause said teletypewriter toV automatically execute a carriage return operation and a line feed operation at the end of each line, and means to prevent said teletypewriter from printing a received dialed digit while executing said line feed operation. V

. PAUL JONES RANK, 

